1 //===--- FrontendActions.cpp ----------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "clang/Frontend/FrontendActions.h"
11 #include "clang/AST/ASTConsumer.h"
12 #include "clang/Basic/FileManager.h"
13 #include "clang/Frontend/ASTConsumers.h"
14 #include "clang/Frontend/ASTUnit.h"
15 #include "clang/Frontend/CompilerInstance.h"
16 #include "clang/Frontend/FrontendDiagnostic.h"
17 #include "clang/Frontend/Utils.h"
18 #include "clang/Lex/HeaderSearch.h"
19 #include "clang/Lex/Pragma.h"
20 #include "clang/Lex/Preprocessor.h"
21 #include "clang/Parse/Parser.h"
22 #include "clang/Serialization/ASTReader.h"
23 #include "clang/Serialization/ASTWriter.h"
24 #include "llvm/Support/FileSystem.h"
25 #include "llvm/Support/MemoryBuffer.h"
26 #include "llvm/Support/raw_ostream.h"
27 #include <memory>
28 #include <system_error>
29 
30 using namespace clang;
31 
32 //===----------------------------------------------------------------------===//
33 // Custom Actions
34 //===----------------------------------------------------------------------===//
35 
36 std::unique_ptr<ASTConsumer>
37 InitOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
38   return llvm::make_unique<ASTConsumer>();
39 }
40 
41 void InitOnlyAction::ExecuteAction() {
42 }
43 
44 //===----------------------------------------------------------------------===//
45 // AST Consumer Actions
46 //===----------------------------------------------------------------------===//
47 
48 std::unique_ptr<ASTConsumer>
49 ASTPrintAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
50   if (raw_ostream *OS = CI.createDefaultOutputFile(false, InFile))
51     return CreateASTPrinter(OS, CI.getFrontendOpts().ASTDumpFilter);
52   return nullptr;
53 }
54 
55 std::unique_ptr<ASTConsumer>
56 ASTDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
57   return CreateASTDumper(CI.getFrontendOpts().ASTDumpFilter,
58                          CI.getFrontendOpts().ASTDumpDecls,
59                          CI.getFrontendOpts().ASTDumpLookups);
60 }
61 
62 std::unique_ptr<ASTConsumer>
63 ASTDeclListAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
64   return CreateASTDeclNodeLister();
65 }
66 
67 std::unique_ptr<ASTConsumer>
68 ASTViewAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
69   return CreateASTViewer();
70 }
71 
72 std::unique_ptr<ASTConsumer>
73 DeclContextPrintAction::CreateASTConsumer(CompilerInstance &CI,
74                                           StringRef InFile) {
75   return CreateDeclContextPrinter();
76 }
77 
78 std::unique_ptr<ASTConsumer>
79 GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
80   std::string Sysroot;
81   std::string OutputFile;
82   raw_ostream *OS = nullptr;
83   if (ComputeASTConsumerArguments(CI, InFile, Sysroot, OutputFile, OS))
84     return nullptr;
85 
86   if (!CI.getFrontendOpts().RelocatablePCH)
87     Sysroot.clear();
88   return llvm::make_unique<PCHGenerator>(CI.getPreprocessor(), OutputFile,
89                                          nullptr, Sysroot, OS);
90 }
91 
92 bool GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
93                                                     StringRef InFile,
94                                                     std::string &Sysroot,
95                                                     std::string &OutputFile,
96                                                     raw_ostream *&OS) {
97   Sysroot = CI.getHeaderSearchOpts().Sysroot;
98   if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
99     CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
100     return true;
101   }
102 
103   // We use createOutputFile here because this is exposed via libclang, and we
104   // must disable the RemoveFileOnSignal behavior.
105   // We use a temporary to avoid race conditions.
106   OS = CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
107                            /*RemoveFileOnSignal=*/false, InFile,
108                            /*Extension=*/"", /*useTemporary=*/true);
109   if (!OS)
110     return true;
111 
112   OutputFile = CI.getFrontendOpts().OutputFile;
113   return false;
114 }
115 
116 std::unique_ptr<ASTConsumer>
117 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
118                                         StringRef InFile) {
119   std::string Sysroot;
120   std::string OutputFile;
121   raw_ostream *OS = nullptr;
122   if (ComputeASTConsumerArguments(CI, InFile, Sysroot, OutputFile, OS))
123     return nullptr;
124 
125   return llvm::make_unique<PCHGenerator>(CI.getPreprocessor(), OutputFile,
126                                          Module, Sysroot, OS);
127 }
128 
129 static SmallVectorImpl<char> &
130 operator+=(SmallVectorImpl<char> &Includes, StringRef RHS) {
131   Includes.append(RHS.begin(), RHS.end());
132   return Includes;
133 }
134 
135 static std::error_code addHeaderInclude(StringRef HeaderName,
136                                         SmallVectorImpl<char> &Includes,
137                                         const LangOptions &LangOpts,
138                                         bool IsExternC) {
139   if (IsExternC && LangOpts.CPlusPlus)
140     Includes += "extern \"C\" {\n";
141   if (LangOpts.ObjC1)
142     Includes += "#import \"";
143   else
144     Includes += "#include \"";
145   // Use an absolute path for the include; there's no reason to think that
146   // a relative path will work (. might not be on our include path) or that
147   // it will find the same file.
148   if (llvm::sys::path::is_absolute(HeaderName)) {
149     Includes += HeaderName;
150   } else {
151     SmallString<256> Header = HeaderName;
152     if (std::error_code Err = llvm::sys::fs::make_absolute(Header))
153       return Err;
154     Includes += Header;
155   }
156   Includes += "\"\n";
157   if (IsExternC && LangOpts.CPlusPlus)
158     Includes += "}\n";
159   return std::error_code();
160 }
161 
162 static std::error_code addHeaderInclude(const FileEntry *Header,
163                                         SmallVectorImpl<char> &Includes,
164                                         const LangOptions &LangOpts,
165                                         bool IsExternC) {
166   return addHeaderInclude(Header->getName(), Includes, LangOpts, IsExternC);
167 }
168 
169 /// \brief Collect the set of header includes needed to construct the given
170 /// module and update the TopHeaders file set of the module.
171 ///
172 /// \param Module The module we're collecting includes from.
173 ///
174 /// \param Includes Will be augmented with the set of \#includes or \#imports
175 /// needed to load all of the named headers.
176 static std::error_code
177 collectModuleHeaderIncludes(const LangOptions &LangOpts, FileManager &FileMgr,
178                             ModuleMap &ModMap, clang::Module *Module,
179                             SmallVectorImpl<char> &Includes) {
180   // Don't collect any headers for unavailable modules.
181   if (!Module->isAvailable())
182     return std::error_code();
183 
184   // Add includes for each of these headers.
185   for (unsigned I = 0, N = Module->NormalHeaders.size(); I != N; ++I) {
186     const FileEntry *Header = Module->NormalHeaders[I];
187     Module->addTopHeader(Header);
188     if (std::error_code Err =
189             addHeaderInclude(Header, Includes, LangOpts, Module->IsExternC))
190       return Err;
191   }
192   // Note that Module->PrivateHeaders will not be a TopHeader.
193 
194   if (const FileEntry *UmbrellaHeader = Module->getUmbrellaHeader()) {
195     Module->addTopHeader(UmbrellaHeader);
196     if (Module->Parent) {
197       // Include the umbrella header for submodules.
198       if (std::error_code Err = addHeaderInclude(UmbrellaHeader, Includes,
199                                                  LangOpts, Module->IsExternC))
200         return Err;
201     }
202   } else if (const DirectoryEntry *UmbrellaDir = Module->getUmbrellaDir()) {
203     // Add all of the headers we find in this subdirectory.
204     std::error_code EC;
205     SmallString<128> DirNative;
206     llvm::sys::path::native(UmbrellaDir->getName(), DirNative);
207     for (llvm::sys::fs::recursive_directory_iterator Dir(DirNative.str(), EC),
208                                                      DirEnd;
209          Dir != DirEnd && !EC; Dir.increment(EC)) {
210       // Check whether this entry has an extension typically associated with
211       // headers.
212       if (!llvm::StringSwitch<bool>(llvm::sys::path::extension(Dir->path()))
213           .Cases(".h", ".H", ".hh", ".hpp", true)
214           .Default(false))
215         continue;
216 
217       // If this header is marked 'unavailable' in this module, don't include
218       // it.
219       if (const FileEntry *Header = FileMgr.getFile(Dir->path())) {
220         if (ModMap.isHeaderUnavailableInModule(Header, Module))
221           continue;
222         Module->addTopHeader(Header);
223       }
224 
225       // Include this header as part of the umbrella directory.
226       if (std::error_code Err = addHeaderInclude(Dir->path(), Includes,
227                                                  LangOpts, Module->IsExternC))
228         return Err;
229     }
230 
231     if (EC)
232       return EC;
233   }
234 
235   // Recurse into submodules.
236   for (clang::Module::submodule_iterator Sub = Module->submodule_begin(),
237                                       SubEnd = Module->submodule_end();
238        Sub != SubEnd; ++Sub)
239     if (std::error_code Err = collectModuleHeaderIncludes(
240             LangOpts, FileMgr, ModMap, *Sub, Includes))
241       return Err;
242 
243   return std::error_code();
244 }
245 
246 bool GenerateModuleAction::BeginSourceFileAction(CompilerInstance &CI,
247                                                  StringRef Filename) {
248   // Find the module map file.
249   const FileEntry *ModuleMap = CI.getFileManager().getFile(Filename);
250   if (!ModuleMap)  {
251     CI.getDiagnostics().Report(diag::err_module_map_not_found)
252       << Filename;
253     return false;
254   }
255 
256   // Parse the module map file.
257   HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
258   if (HS.loadModuleMapFile(ModuleMap, IsSystem))
259     return false;
260 
261   if (CI.getLangOpts().CurrentModule.empty()) {
262     CI.getDiagnostics().Report(diag::err_missing_module_name);
263 
264     // FIXME: Eventually, we could consider asking whether there was just
265     // a single module described in the module map, and use that as a
266     // default. Then it would be fairly trivial to just "compile" a module
267     // map with a single module (the common case).
268     return false;
269   }
270 
271   // If we're being run from the command-line, the module build stack will not
272   // have been filled in yet, so complete it now in order to allow us to detect
273   // module cycles.
274   SourceManager &SourceMgr = CI.getSourceManager();
275   if (SourceMgr.getModuleBuildStack().empty())
276     SourceMgr.pushModuleBuildStack(CI.getLangOpts().CurrentModule,
277                                    FullSourceLoc(SourceLocation(), SourceMgr));
278 
279   // Dig out the module definition.
280   Module = HS.lookupModule(CI.getLangOpts().CurrentModule,
281                            /*AllowSearch=*/false);
282   if (!Module) {
283     CI.getDiagnostics().Report(diag::err_missing_module)
284       << CI.getLangOpts().CurrentModule << Filename;
285 
286     return false;
287   }
288 
289   // Check whether we can build this module at all.
290   clang::Module::Requirement Requirement;
291   clang::Module::HeaderDirective MissingHeader;
292   if (!Module->isAvailable(CI.getLangOpts(), CI.getTarget(), Requirement,
293                            MissingHeader)) {
294     if (MissingHeader.FileNameLoc.isValid()) {
295       CI.getDiagnostics().Report(MissingHeader.FileNameLoc,
296                                  diag::err_module_header_missing)
297         << MissingHeader.IsUmbrella << MissingHeader.FileName;
298     } else {
299       CI.getDiagnostics().Report(diag::err_module_unavailable)
300         << Module->getFullModuleName()
301         << Requirement.second << Requirement.first;
302     }
303 
304     return false;
305   }
306 
307   if (ModuleMapForUniquing && ModuleMapForUniquing != ModuleMap) {
308     Module->IsInferred = true;
309     HS.getModuleMap().setInferredModuleAllowedBy(Module, ModuleMapForUniquing);
310   } else {
311     ModuleMapForUniquing = ModuleMap;
312   }
313 
314   FileManager &FileMgr = CI.getFileManager();
315 
316   // Collect the set of #includes we need to build the module.
317   SmallString<256> HeaderContents;
318   std::error_code Err = std::error_code();
319   if (const FileEntry *UmbrellaHeader = Module->getUmbrellaHeader())
320     Err = addHeaderInclude(UmbrellaHeader, HeaderContents, CI.getLangOpts(),
321                            Module->IsExternC);
322   if (!Err)
323     Err = collectModuleHeaderIncludes(
324         CI.getLangOpts(), FileMgr,
325         CI.getPreprocessor().getHeaderSearchInfo().getModuleMap(), Module,
326         HeaderContents);
327 
328   if (Err) {
329     CI.getDiagnostics().Report(diag::err_module_cannot_create_includes)
330       << Module->getFullModuleName() << Err.message();
331     return false;
332   }
333 
334   llvm::MemoryBuffer *InputBuffer =
335       llvm::MemoryBuffer::getMemBufferCopy(HeaderContents,
336                                            Module::getModuleInputBufferName());
337   // Ownership of InputBuffer will be transferred to the SourceManager.
338   setCurrentInput(FrontendInputFile(InputBuffer, getCurrentFileKind(),
339                                     Module->IsSystem));
340   return true;
341 }
342 
343 bool GenerateModuleAction::ComputeASTConsumerArguments(CompilerInstance &CI,
344                                                        StringRef InFile,
345                                                        std::string &Sysroot,
346                                                        std::string &OutputFile,
347                                                        raw_ostream *&OS) {
348   // If no output file was provided, figure out where this module would go
349   // in the module cache.
350   if (CI.getFrontendOpts().OutputFile.empty()) {
351     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
352     CI.getFrontendOpts().OutputFile =
353         HS.getModuleFileName(CI.getLangOpts().CurrentModule,
354                              ModuleMapForUniquing->getName());
355   }
356 
357   // We use createOutputFile here because this is exposed via libclang, and we
358   // must disable the RemoveFileOnSignal behavior.
359   // We use a temporary to avoid race conditions.
360   OS = CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
361                            /*RemoveFileOnSignal=*/false, InFile,
362                            /*Extension=*/"", /*useTemporary=*/true,
363                            /*CreateMissingDirectories=*/true);
364   if (!OS)
365     return true;
366 
367   OutputFile = CI.getFrontendOpts().OutputFile;
368   return false;
369 }
370 
371 std::unique_ptr<ASTConsumer>
372 SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
373   return llvm::make_unique<ASTConsumer>();
374 }
375 
376 std::unique_ptr<ASTConsumer>
377 DumpModuleInfoAction::CreateASTConsumer(CompilerInstance &CI,
378                                         StringRef InFile) {
379   return llvm::make_unique<ASTConsumer>();
380 }
381 
382 std::unique_ptr<ASTConsumer>
383 VerifyPCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
384   return llvm::make_unique<ASTConsumer>();
385 }
386 
387 void VerifyPCHAction::ExecuteAction() {
388   CompilerInstance &CI = getCompilerInstance();
389   bool Preamble = CI.getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
390   const std::string &Sysroot = CI.getHeaderSearchOpts().Sysroot;
391   std::unique_ptr<ASTReader> Reader(
392       new ASTReader(CI.getPreprocessor(), CI.getASTContext(),
393                     Sysroot.empty() ? "" : Sysroot.c_str(),
394                     /*DisableValidation*/ false,
395                     /*AllowPCHWithCompilerErrors*/ false,
396                     /*AllowConfigurationMismatch*/ true,
397                     /*ValidateSystemInputs*/ true));
398 
399   Reader->ReadAST(getCurrentFile(),
400                   Preamble ? serialization::MK_Preamble
401                            : serialization::MK_PCH,
402                   SourceLocation(),
403                   ASTReader::ARR_ConfigurationMismatch);
404 }
405 
406 namespace {
407   /// \brief AST reader listener that dumps module information for a module
408   /// file.
409   class DumpModuleInfoListener : public ASTReaderListener {
410     llvm::raw_ostream &Out;
411 
412   public:
413     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
414 
415 #define DUMP_BOOLEAN(Value, Text)                       \
416     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
417 
418     bool ReadFullVersionInformation(StringRef FullVersion) override {
419       Out.indent(2)
420         << "Generated by "
421         << (FullVersion == getClangFullRepositoryVersion()? "this"
422                                                           : "a different")
423         << " Clang: " << FullVersion << "\n";
424       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
425     }
426 
427     void ReadModuleName(StringRef ModuleName) override {
428       Out.indent(2) << "Module name: " << ModuleName << "\n";
429     }
430     void ReadModuleMapFile(StringRef ModuleMapPath) override {
431       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
432     }
433 
434     bool ReadLanguageOptions(const LangOptions &LangOpts,
435                              bool Complain) override {
436       Out.indent(2) << "Language options:\n";
437 #define LANGOPT(Name, Bits, Default, Description) \
438       DUMP_BOOLEAN(LangOpts.Name, Description);
439 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
440       Out.indent(4) << Description << ": "                   \
441                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
442 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
443       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
444 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
445 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
446 #include "clang/Basic/LangOptions.def"
447       return false;
448     }
449 
450     bool ReadTargetOptions(const TargetOptions &TargetOpts,
451                            bool Complain) override {
452       Out.indent(2) << "Target options:\n";
453       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
454       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
455       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
456 
457       if (!TargetOpts.FeaturesAsWritten.empty()) {
458         Out.indent(4) << "Target features:\n";
459         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
460              I != N; ++I) {
461           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
462         }
463       }
464 
465       return false;
466     }
467 
468     virtual bool
469     ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
470                           bool Complain) override {
471       Out.indent(2) << "Diagnostic options:\n";
472 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
473 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
474       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
475 #define VALUE_DIAGOPT(Name, Bits, Default) \
476       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
477 #include "clang/Basic/DiagnosticOptions.def"
478 
479       Out.indent(4) << "Diagnostic flags:\n";
480       for (const std::string &Warning : DiagOpts->Warnings)
481         Out.indent(6) << "-W" << Warning << "\n";
482       for (const std::string &Remark : DiagOpts->Remarks)
483         Out.indent(6) << "-R" << Remark << "\n";
484 
485       return false;
486     }
487 
488     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
489                                  bool Complain) override {
490       Out.indent(2) << "Header search options:\n";
491       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
492       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
493                    "Use builtin include directories [-nobuiltininc]");
494       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
495                    "Use standard system include directories [-nostdinc]");
496       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
497                    "Use standard C++ include directories [-nostdinc++]");
498       DUMP_BOOLEAN(HSOpts.UseLibcxx,
499                    "Use libc++ (rather than libstdc++) [-stdlib=]");
500       return false;
501     }
502 
503     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
504                                  bool Complain,
505                                  std::string &SuggestedPredefines) override {
506       Out.indent(2) << "Preprocessor options:\n";
507       DUMP_BOOLEAN(PPOpts.UsePredefines,
508                    "Uses compiler/target-specific predefines [-undef]");
509       DUMP_BOOLEAN(PPOpts.DetailedRecord,
510                    "Uses detailed preprocessing record (for indexing)");
511 
512       if (!PPOpts.Macros.empty()) {
513         Out.indent(4) << "Predefined macros:\n";
514       }
515 
516       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
517              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
518            I != IEnd; ++I) {
519         Out.indent(6);
520         if (I->second)
521           Out << "-U";
522         else
523           Out << "-D";
524         Out << I->first << "\n";
525       }
526       return false;
527     }
528 #undef DUMP_BOOLEAN
529   };
530 }
531 
532 void DumpModuleInfoAction::ExecuteAction() {
533   // Set up the output file.
534   std::unique_ptr<llvm::raw_fd_ostream> OutFile;
535   StringRef OutputFileName = getCompilerInstance().getFrontendOpts().OutputFile;
536   if (!OutputFileName.empty() && OutputFileName != "-") {
537     std::string ErrorInfo;
538     OutFile.reset(new llvm::raw_fd_ostream(OutputFileName.str().c_str(),
539                                            ErrorInfo, llvm::sys::fs::F_Text));
540   }
541   llvm::raw_ostream &Out = OutFile.get()? *OutFile.get() : llvm::outs();
542 
543   Out << "Information for module file '" << getCurrentFile() << "':\n";
544   DumpModuleInfoListener Listener(Out);
545   ASTReader::readASTFileControlBlock(getCurrentFile(),
546                                      getCompilerInstance().getFileManager(),
547                                      Listener);
548 }
549 
550 //===----------------------------------------------------------------------===//
551 // Preprocessor Actions
552 //===----------------------------------------------------------------------===//
553 
554 void DumpRawTokensAction::ExecuteAction() {
555   Preprocessor &PP = getCompilerInstance().getPreprocessor();
556   SourceManager &SM = PP.getSourceManager();
557 
558   // Start lexing the specified input file.
559   const llvm::MemoryBuffer *FromFile = SM.getBuffer(SM.getMainFileID());
560   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
561   RawLex.SetKeepWhitespaceMode(true);
562 
563   Token RawTok;
564   RawLex.LexFromRawLexer(RawTok);
565   while (RawTok.isNot(tok::eof)) {
566     PP.DumpToken(RawTok, true);
567     llvm::errs() << "\n";
568     RawLex.LexFromRawLexer(RawTok);
569   }
570 }
571 
572 void DumpTokensAction::ExecuteAction() {
573   Preprocessor &PP = getCompilerInstance().getPreprocessor();
574   // Start preprocessing the specified input file.
575   Token Tok;
576   PP.EnterMainSourceFile();
577   do {
578     PP.Lex(Tok);
579     PP.DumpToken(Tok, true);
580     llvm::errs() << "\n";
581   } while (Tok.isNot(tok::eof));
582 }
583 
584 void GeneratePTHAction::ExecuteAction() {
585   CompilerInstance &CI = getCompilerInstance();
586   if (CI.getFrontendOpts().OutputFile.empty() ||
587       CI.getFrontendOpts().OutputFile == "-") {
588     // FIXME: Don't fail this way.
589     // FIXME: Verify that we can actually seek in the given file.
590     llvm::report_fatal_error("PTH requires a seekable file for output!");
591   }
592   llvm::raw_fd_ostream *OS =
593     CI.createDefaultOutputFile(true, getCurrentFile());
594   if (!OS) return;
595 
596   CacheTokens(CI.getPreprocessor(), OS);
597 }
598 
599 void PreprocessOnlyAction::ExecuteAction() {
600   Preprocessor &PP = getCompilerInstance().getPreprocessor();
601 
602   // Ignore unknown pragmas.
603   PP.IgnorePragmas();
604 
605   Token Tok;
606   // Start parsing the specified input file.
607   PP.EnterMainSourceFile();
608   do {
609     PP.Lex(Tok);
610   } while (Tok.isNot(tok::eof));
611 }
612 
613 void PrintPreprocessedAction::ExecuteAction() {
614   CompilerInstance &CI = getCompilerInstance();
615   // Output file may need to be set to 'Binary', to avoid converting Unix style
616   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>).
617   //
618   // Look to see what type of line endings the file uses. If there's a
619   // CRLF, then we won't open the file up in binary mode. If there is
620   // just an LF or CR, then we will open the file up in binary mode.
621   // In this fashion, the output format should match the input format, unless
622   // the input format has inconsistent line endings.
623   //
624   // This should be a relatively fast operation since most files won't have
625   // all of their source code on a single line. However, that is still a
626   // concern, so if we scan for too long, we'll just assume the file should
627   // be opened in binary mode.
628   bool BinaryMode = true;
629   bool InvalidFile = false;
630   const SourceManager& SM = CI.getSourceManager();
631   const llvm::MemoryBuffer *Buffer = SM.getBuffer(SM.getMainFileID(),
632                                                      &InvalidFile);
633   if (!InvalidFile) {
634     const char *cur = Buffer->getBufferStart();
635     const char *end = Buffer->getBufferEnd();
636     const char *next = (cur != end) ? cur + 1 : end;
637 
638     // Limit ourselves to only scanning 256 characters into the source
639     // file.  This is mostly a sanity check in case the file has no
640     // newlines whatsoever.
641     if (end - cur > 256) end = cur + 256;
642 
643     while (next < end) {
644       if (*cur == 0x0D) {  // CR
645         if (*next == 0x0A)  // CRLF
646           BinaryMode = false;
647 
648         break;
649       } else if (*cur == 0x0A)  // LF
650         break;
651 
652       ++cur, ++next;
653     }
654   }
655 
656   raw_ostream *OS = CI.createDefaultOutputFile(BinaryMode, getCurrentFile());
657   if (!OS) return;
658 
659   DoPrintPreprocessedInput(CI.getPreprocessor(), OS,
660                            CI.getPreprocessorOutputOpts());
661 }
662 
663 void PrintPreambleAction::ExecuteAction() {
664   switch (getCurrentFileKind()) {
665   case IK_C:
666   case IK_CXX:
667   case IK_ObjC:
668   case IK_ObjCXX:
669   case IK_OpenCL:
670   case IK_CUDA:
671     break;
672 
673   case IK_None:
674   case IK_Asm:
675   case IK_PreprocessedC:
676   case IK_PreprocessedCXX:
677   case IK_PreprocessedObjC:
678   case IK_PreprocessedObjCXX:
679   case IK_AST:
680   case IK_LLVM_IR:
681     // We can't do anything with these.
682     return;
683   }
684 
685   CompilerInstance &CI = getCompilerInstance();
686   llvm::MemoryBuffer *Buffer
687       = CI.getFileManager().getBufferForFile(getCurrentFile());
688   if (Buffer) {
689     unsigned Preamble =
690         Lexer::ComputePreamble(Buffer->getBuffer(), CI.getLangOpts()).first;
691     llvm::outs().write(Buffer->getBufferStart(), Preamble);
692     delete Buffer;
693   }
694 }
695